• British Pharmacopoeia Volume V
  • Appendices
  • Appendix I A. General Reagents

Chloroform
scroll to previous hit
scroll to next hit

Chloroform Trichloromethane; CHCl3 = 119.4 (67-66-3)

Clear, colourless liquid, slightly soluble in water, miscible with ethanol (96%).

bp2013_v5_47_1003_[appendix_i_a]_c_ep7-7_ep_revised_texts d_20_20.png, 1.475 to 1.481; boiling point, about 60°.

Ethanol 0.4% w/w to 1.0% w/w.

Introduce 1.00 g (m g) into a ground-glass-stoppered flask. Add 15.0 mL of nitrochromic reagent, close the flask, shake vigorously for 2 minutes and allow to stand for 15 minutes. Add 100 mL of water and 5 mL of a 200 g/L solution of potassium iodide. After 2 minutes titrate with 0.1 M sodium thiosulfate, using 1 mL of starch solution as indicator, until a light green colour is obtained (n1 mL of 0.1 M sodium thiosulfate). Carry out a blank assay (n2 mL of 0.1 M sodium thiosulfate). Calculate the percentage of ethanol using the following expression :

bp2013_v5_47_1003_[appendix_i_a]_c_ep7-7_ep_revised_texts appia_chloroform_1_bp2012_eq.png